The Tor Browser / file diff

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/addon-sdk/source/lib/sdk/event/target.js	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,76 @@
     1.4 +/* This Source Code Form is subject to the terms of the Mozilla Public
     1.5 + * License, v. 2.0. If a copy of the MPL was not distributed with this
     1.6 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
     1.7 +
     1.8 +'use strict';
     1.9 +
    1.10 +module.metadata = {
    1.11 +  "stability": "stable"
    1.12 +};
    1.13 +
    1.14 +const { on, once, off, setListeners } = require('./core');
    1.15 +const { method, chainable } = require('../lang/functional');
    1.16 +const { Class } = require('../core/heritage');
    1.17 +
    1.18 +/**
    1.19 + * `EventTarget` is an exemplar for creating an objects that can be used to
    1.20 + * add / remove event listeners on them. Events on these objects may be emitted
    1.21 + * via `emit` function exported by 'event/core' module.
    1.22 + */
    1.23 +const EventTarget = Class({
    1.24 +  /**
    1.25 +   * Method initializes `this` event source. It goes through properties of a
    1.26 +   * given `options` and registers listeners for the ones that look like an
    1.27 +   * event listeners.
    1.28 +   */
    1.29 +  /**
    1.30 +   * Method initializes `this` event source. It goes through properties of a
    1.31 +   * given `options` and registers listeners for the ones that look like an
    1.32 +   * event listeners.
    1.33 +   */
    1.34 +  initialize: function initialize(options) {
    1.35 +    setListeners(this, options);
    1.36 +  },
    1.37 +  /**
    1.38 +   * Registers an event `listener` that is called every time events of
    1.39 +   * specified `type` are emitted.
    1.40 +   * @param {String} type
    1.41 +   *    The type of event.
    1.42 +   * @param {Function} listener
    1.43 +   *    The listener function that processes the event.
    1.44 +   * @example
    1.45 +   *      worker.on('message', function (data) {
    1.46 +   *        console.log('data received: ' + data)
    1.47 +   *      })
    1.48 +   */
    1.49 +  on: chainable(method(on)),
    1.50 +  /**
    1.51 +   * Registers an event `listener` that is called once the next time an event
    1.52 +   * of the specified `type` is emitted.
    1.53 +   * @param {String} type
    1.54 +   *    The type of the event.
    1.55 +   * @param {Function} listener
    1.56 +   *    The listener function that processes the event.
    1.57 +   */
    1.58 +  once: chainable(method(once)),
    1.59 +  /**
    1.60 +   * Removes an event `listener` for the given event `type`.
    1.61 +   * @param {String} type
    1.62 +   *    The type of event.
    1.63 +   * @param {Function} listener
    1.64 +   *    The listener function that processes the event.
    1.65 +   */
    1.66 +  removeListener: function removeListener(type, listener) {
    1.67 +    // Note: We can't just wrap `off` in `method` as we do it for other methods
    1.68 +    // cause skipping a second or third argument will behave very differently
    1.69 +    // than intended. This way we make sure all arguments are passed and only
    1.70 +    // one listener is removed at most.
    1.71 +    off(this, type, listener);
    1.72 +    return this;
    1.73 +  },
    1.74 +  off: function(type, listener) {
    1.75 +    off(this, type, listener);
    1.76 +    return this;
    1.77 +  }
    1.78 +});
    1.79 +exports.EventTarget = EventTarget;